Looks like you have fallen into the same trap as I did Ian. Ordered solder paste online and got the same as you - solder flux.

I did eventually get the proper stuff while rebuilding Smit Nederland. Some suppliers are now changing their product information and calling it Solder Paint, which makes sense because you simply "paint" it on and use very little amounts. A few times I used a cocktail stick to apply in awkward corners.
Also, John (cos918) is correct in saying it is silver coloured, rather dull silver actually.
The "paint" or "paste" is made of micro balls of solder, mixed with flux, ready to use. The tub I bought has a use by of Feb 2018 so I'll have to get cracking and get lots of soldering jobs lined up.

....and you were right to go for the smaller amounts by the way.

Regards,
Ray.